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<H2><A NAME="SECTION03518000000000000000"></A>                               <A NAME="lworkquery"></A>
<BR>
LWORK Query
</H2>
 
If in doubt about the amount of workspace to supply to an LAPACK
routine, the user may choose to supply <B><I>LWORK</I>=-1</B><A NAME="19559"></A>
and use the returned value in <B><I>WORK</I>(1)</B> as the correct value
for <B><I>LWORK</I></B>.  Setting <B><I>LWORK</I>=-1</B> does not invoke an error message
from <TT>XERBLA</TT> and is defined as a global
query<A NAME="19561"></A><A NAME="19562"></A><A NAME="19563"></A>.

<P>
The routines xGEESX and xGGESX are the only exceptions to this rule.
For these routines, the value of LWORK is dependent upon the dimension
of the invariant subspace (SDIM), and is not known on entry to the routine.

<P>
<BR><HR>
<ADDRESS>
<I>Susan Blackford</I>
<BR><I>1999-10-01</I>
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